How to get rid of a legacy app?

Hello,

i built my first rails app 6 years ago and there is a lot of things I want to get rid of. The app is still running and actually generating revenue! But it is basically not maintainable anymore - at least in my opinion.
At the moment I have the feeling it is easier to start with a clean slate, Rails 7, esbuild, tailwind and so on.

My plan is to build the new version, deploy it to Heroku and just link it to the old database on Heroku.

But how do I handle the database stuff?

Option A: Copying over all the old migration files?
Option B: Not copying the files and just using the schema.rb in development?

Is there another option? What is your experience with this?